The present invention relates to a camera incorporating a focal-plane shutter.
In certain conventional cameras, the photometry is achieved by measuring a light intensity reflected from the focal-plane shutter, using the photometry means. For instance, as shown in FIG. 30(a), photometry means 1000 is disposed at substantially the lower center position of image window 1001, or at the upper corner position of image window 1001 as shown in FIG. 30(b).
Accordingly, the photometric region measured by the above photometry means is limited in an elliptical region covered by the aperture of the photometry means disposed at either the lower center position or the upper corner position. Therefore, the efficiency of the photometry means decreases at a rate of uncovered region in the image window, since the major axis of the elliptical region does not coincide with the longer axis of the image window.
Further, since the focal-plane shutter, incorporated in the above conventional cameras, is not integrally mounted with the photometry means and the dating means, the positioning process of the photometry means and the dating means relative to the image window should be performed after combining them with the image window. Therefore, readjustment of the photometry means and the dating means is necessary, after reassembling them into the camera, for instance, at the time of maintenance works.
In addition, in the above conventional cameras, error occurrences of the focal-plane shutter cannot be detected.
To overcome the abovementioned drawbacks in conventional cameras, the first object of the present invention is to provide a camera which makes it possible to perform a precise photometry, and the second object of the present invention is to provide a camera in which an assembling process is simplified and improved, the third object of the present invention is to provide a camera which makes it possible to detect an error of the focal-plane shutter.
Accordingly, to overcome the cited shortcomings, the abovementioned objects of the present invention can be attained by cameras described as follow.
(1) A camera, comprising a lens, an image window having an aperture to bound a light coming through the lens in a plain perpendicular to an optical axis of the lens, a focal-plane shutter and a photometry sensor to receive the light reflected by the focal-plane shutter and detect an amount of the light reflected by the focal-plane shutter after coming through the lens, wherein the photometry sensor is located at an outside of the aperture and resides on a plane, which is parallel with the optical axis and includes a line which is parallel to a long-axis of the aperture and passes substantially a center of a short-axis of the aperture.
(2) The camera of item 1, wherein the photometry sensor is located outside a light path through which the light, entering from the lens, travels to the aperture.
(3) The camera of item 1, further comprising a photometry aperture control to set a photometry range, the photometry aperture control is disposed in an optical path through which the light, reflected by the focal-plane shutter, travels to the photometry sensor.
(4) The camera of item 3, further comprising a finder and a photometry range display, disposed in the finder, to display the photometry range set by the photometry aperture control.
(5) The camera of item 1, further comprising a processor to obtain parameters in regard to an exposure control, based on an amount of the light detected by the photometry sensor.
(6) The camera of item 1, wherein the photometry sensor is integrally arranged in a shutter unit which comprises the focal-plane shutter.
(7) The camera of item 1, further comprising a date projector to project a date on a film loaded in the camera, the date projector is integrally arranged in a shutter unit which comprises the focal-plane shutter.
(8) The camera of item 1, further comprising a X-switch signal sensor to detect a signal of a X-switch mounted in the focal-plane shutter and a controller to perform error jobs, when the X-switch signal sensor does not detect the signal within a predetermined time after activating a shutter release button.
(9) A camera, comprising a lens, a shutter unit comprising a focal-plane shutter and a photometry sensor to receive and detect an amount of a light reflected by the focal-plane shutter after coming through the lens, the photometry sensor is integrally arranged in the shutter unit.
(10) A camera, comprising a lens, a shutter unit comprising a focal-plane shutter and a date projector to project a date on a film loaded in the camera, the date projector is integrally arranged in the shutter unit.
(11) A camera, comprising a lens, a focal-plane shutter, a X-switch signal sensor to detect a signal of a X-switch and a controller to perform error jobs, when the X-switch signal sensor does not detect the signal within a predetermined time after activating a shutter release button.
Further, to overcome the abovementioned problems, other cameras, embodied in the present invention, will be described as follow:
(12) A camera, characterized in that said camera performs a photometry by means of a photometry means which receives a light coming through the lens and reflected by the focal-plane shutter, and the photometry means is arranged at substantially a center side position of a short-axis of the aperture, viewing from a photographic lens side.
According to the camera described in item 12, the photometry efficiency can be improved by arranging the photometry means at substantially a center side position of a short-axis of the aperture, viewing from a photographic lens side, and by aligning a photometry region in a direction of the aperture.
(13) The camera of item 12, characterized in that the camera further comprises a photometry aperture means to set a photometry range, and the photometry aperture means is disposed in an optical path through which the light, reflected by the focal-plane shutter, travels to the photometry means.
According to the camera described in item 13, since a variable photometry can be achieved by varying the photometric region in an optical path, through which the light, reflected by the focal-plane shutter, enters into photometry means, it becomes possible for a photographer to select a suitable photometric region corresponding to the scene to be shot.
(14) The camera of item 13, characterized in that the camera further comprises a photometry range display means, disposed in a finder, to display the photometry range set by the photometry aperture means.
According to the camera described in item 14, since the photometric region is displayed on the photometric region display means disposed in the finder, it becomes possible for the photographer to easily select the desirable photometric region.
(15) A camera, characterized in that said camera performs a photometry by means of a photometry means which receives a light coming through a photographic lens and reflected by a focal-plane shutter, and a photometry means is integrally arranged in a focal-plane shutter unit which comprises the focal-plane shutter.
According to the camera described in item 15, since the photometry means is integrally assembled with the focal-plane shutter unit, it is possible to adjust the relative position between the focal-plane shutter and the photometry means in a state of unit. Therefore, it becomes possible to detect failed units and to precisely assemble the units before assembling the focal-plane shutter unit in the camera body.
(16) A camera, characterized in that said camera performs a photometry by means of a photometry means which receives a light coming through a photographic lens and reflected by a focal-plane shutter, and a dating means is integrally arranged in a focal-plane shutter unit which comprises the focal-plane shutter.
According to the camera described in item 16, since the dating means is integrally assembled with the focal-plane shutter unit, it is possible to adjust the relative position between the focal-plane shutter and the dating means in a state of unit. Therefore, the readjustment of the relative position between them is not necessarily when performing maintenance works.
(17) A camera, characterized in that said camera comprises a focal-plane shutter, a X-switch signal detecting means to detect a signal of a X-switch and a control means to perform error jobs, when the X-switch signal detecting means does not detect the signal of the X-switch within a predetermined time after activating a shutter release button.
According to the camera described in item 17, in regard to the camera in which the X switch turns ON only when the succeeding shutter blind completely running through the aperture, it is possible to detect an error state caused by a certain malfunction, when the X switch does not turns ON within the predetermined time after the succeeding blind starts running. Thus, the photographer can easily perceive the error state of the camera, even when an image capturing becomes impossible due to a certain malfunction in the focal-plane shutter.